A layer of silver is, for example, printed on those plates in order to construct solar collectors.
Those plates are processed by various machines which are provided one behind the other in a linear processing line. The printing step is carried out in the middle of other processing steps so that the printing machine comprises at least a station for introducing the object, a station for printing and a station for discharging the object separate from the introduction station.
In this type of printing machine, the objects to be printed are brought to the introduction station of the printing machine by an introduction conveyor. The objects are moved from the introduction conveyor towards the tower by a transfer device which is carried by the tower. Subsequently, the objects are moved by the tower being rotated towards the printing station, then towards the discharge station of the tower. Finally, the transfer device transports the object towards a discharge conveyor. Therefore, the tower carries a number of transfer devices and a number of means for driving those transfer devices that is equal to the number of stations of the machine. Since the machine comprises an introduction station, a printing station and a discharge station, this number is a minimum of three.
Consequently, this type of machine takes up a large amount of space. This type of machine further requires means for rotating the tower which are powerful owing to the great weight thereof.